A 5.6µm Stacked Voltage Domain Global Shutter Pixel with 88ke- Linear Full Well Capacity and 85dB Single Exposure High Dynamic Range
2021 International Image Sensor Workshop (IISW)
In this paper, design and characterization of a 5.6µm stacked voltage mode (VM) global shutter (GS) pixel with a multiple conversion gain (CG) switching function and a high charge density photodiode (PD) is reported. Through study and analysis on several types of pixel structures, an optimum PD structure has been identified to obtain high full well capacity without image lag, where 2 PDs are formed in a pixel, and in each PD, a p-type separation layer and an n-type gradient profile are formed. In conclusion, a high linear full well capacity (LFWC) of 88ke- with good charge transfer performance was obtained with a 5.6µm stacked GS pixel. With a dual CG and the split PD structure, the pixel provides 85dB single exposure high dynamic range (SEHDR) and the phase detection auto focus (PDAF) capability.